For all his sound and fury on the stage, Ballmer often doesn't take the high-risk, high-reward chances necessary to become a star. If he assumes his conservative stance this time, Microsoft's newly announced Surface tablet will likely suffer the same fate as the lackluster Bing, Zune, Origami, Mira, Portable Media Center and, most devastatingly, Windows Phone.

"Ballmer has a tendency with money to underfund everything, taking a required launch budget and cutting it by two-thirds," says tech analyst Rob Enderle. "I am worried that he's going to repeat this mistake of being cheap, and being cheap won't get this done."

This week, , a Windows tablet with a 10.6-inch screen, that will come in a version running Windows RT and a business-oriented version running Windows 8 Pro. It will be a premium product likely cost compatible with the iPad and sold concierge-style at Microsoft retail stores starting in the fall.

Surface just may be Microsoft's defining moment-for good or ill.

Microsoft has already taken a huge risk with Surface by breaking from tradition and melding software and hardware. By getting into the hardware side of a product that competes with PCs, Microsoft alienates its PC partners. When how Microsoft's PC partners felt about the Surface, Ballmer responded, "No comment."